Downlink control channel structure for low latency applications

ABSTRACT

Methods, systems, and devices for wireless communication are described. In one example, an indication in a first control message in a control region of a first transmission time interval (TTI) identifies a data region of the first TTI. A data region of the second TTI may be identified based on a grant of resources received in a second control message of a second TTI, where the data region of the first TTI and the control region of the second TTI are frequency division multiplexed with the data region of the second TTI. Other examples include a downlink grant at the beginning of a control region and uplink grants at the end of the control region. In other examples, a downlink grant for a user equipment (UE) may include an indication of resources allocated to the UE in that resource block and a second resource block.

CROSS REFERENCES

The present Application for Patent claims priority to U.S. ProvisionalPatent Application No. 62/374,607, entitled “Downlink Control ChannelStructure For Low Latency Applications,” filed Aug. 12, 2016, assignedto the assignee hereof.

BACKGROUND

The following relates generally to wireless communication, and morespecifically to a downlink control channel structure for low latencyapplications.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include code division multiple access (CDMA)systems, time division multiple access (TDMA) systems, frequencydivision multiple access (FDMA) systems, and orthogonal frequencydivision multiple access (OFDMA) systems, (e.g., a Long Term Evolution(LTE) system). A wireless multiple-access communications system mayinclude a number of base stations, each simultaneously supportingcommunication for multiple communication devices, which may be known asuser equipments (UEs).

Wireless multiple-access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent wireless devices to communicate on a municipal, national,regional, and even global level. LTE is an example of atelecommunication standard. LTE is designed to improve spectralefficiency, lower costs, improve services, make use of new spectrum, andbetter integrate with other open standards. LTE may use OFDMA on thedownlink (DL), single-carrier frequency division multiple access(SC-FDMA) on the uplink (UL), and multiple-input multiple-output (MIMO)antenna technology.

A base station may transmit to one or more UEs using a transmission timeinterval (TTI) that is reduced in length. Such a TTI may be referred toas a shortened TTI (sTTI) and a user receiving a sTTI may be a lowlatency user. A sTTI may be divided into a number of resource blocksacross a system bandwidth, and each of the resource blocks may beallocated to a UE by a base station. The base station may transmitcontrol information or a control message in a first portion of theresource block to provide the resource allocations. A low latency usermay attempt to decode the control information in the resource block. AssTTIs become shorter, it is ever more important to reduce the controloverhead. Thus, it is desirable to efficiently communicate controlinformation, and minimize the amount of processing time required for aUE to receive and decode the control information.

SUMMARY

A base station may indicate time and frequency resources fortransmission of a low latency physical downlink control channel (sPDCCH)to a user equipment (UE). A first transmission time interval (TTI) mayinclude a control region, for example, a physical downlink controlchannel (PDCCH) that includes an indication of a data region within thefirst TTI. The data region of the first TTI may be for a physicaldownlink shared channel (PDSCH), narrowband internet-of-things (NB-IOT)type transmission, or common signaling transmission transmitted by abase station. The first TTI may overlap at least in part with a secondTTI. The second TTI may be a shortened TTI (sTTI) made up of one or moreresource blocks for low latency transmissions, where the data regionwithin the first TTI punctures or otherwise falls within one or more ofthe resource blocks of the second TTI. A control region of the secondTTI may be a sPDCCH. The control region of the PDCCH may include acontrol message that has a grant of downlink resources for the lowlatency UE, where the grant indicates a data region of a resource blockof the second TTI such that the indicated data region is frequencydivision multiplexed with the data region of the first TTI. The basestation may identify the data region of the first TTI and the dataregion for the receiving low latency UE, and rate match around the dataregion of the first TTI to receive low latency data in the data regionof the second TTI.

In other examples, a downlink grant transmitted in the control region ofa resource block may be for both the resource block in which thedownlink grant is sent by a base station and, for a second resourceblock within the same TTI. In some cases, the downlink grant may includean indication to the UE, such as a number of bits to inform the UE thatthe downlink grant is also for the UE to receive data in a data regionof one or more of the other resource blocks in the TTI, in addition toreceiving data in the data region of the resource block in which thedownlink grant was received.

The control region for the low latency UE may also include one or moreuplink grants. In some cases, at least one of the uplink grants may befor the same UE as was the previously indicated downlink grant. In someother cases, the one or more uplink grants may be for different UEs. Thedownlink grant may be at the beginning of the control region, forexample, at a first boundary of the control region, and the one or moreuplink grants may be at the end of the control region, for example, at asecond boundary of the control region. An unused portion of the controlregion may be reallocated to the data region. An indication of the startof the uplink grants may be provided in the downlink grant to allow theUE to identify the reallocated data region within the control region.

A method of wireless communication is described. The method may includereceiving a first control message within a control region of a first TTIthat has a first duration, identifying a data region of the first TTIbased at least in part on an indication received in the first controlmessage, receiving a second control message within a control region of asecond TTI that has a second duration that is less than the firstduration, wherein the first TTI and the second TTI at least partiallyoverlap in time, and receiving data in a data region of the second TTIbased at least in part on a grant of resources received in the secondcontrol message, wherein the data region of the first TTI is frequencydivision multiplexed with the data region of the second TTI, and whereinthe control region of the second TTI is frequency division multiplexedwith the data region of the second TTI.

An apparatus for wireless communication is described. The apparatus mayinclude means for receiving a first control message within a controlregion of a first TTI that has a first duration, means for identifying adata region of the first TTI based at least in part on an indicationreceived in the first control message, means for receiving a secondcontrol message within a control region of a second TTI that has asecond duration that is less than the first duration, wherein the firstTTI and the second TTI at least partially overlap in time, and means forreceiving data in a data region of the second TTI based at least in parton a grant of resources received in the second control message, whereinthe data region of the first TTI is frequency division multiplexed withthe data region of the second TTI, and wherein the control region of thesecond TTI is frequency division multiplexed with the data region of thesecond TTI.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to receive a first control messagewithin a control region of a first TTI that has a first duration,identify a data region of the first TTI based at least in part on anindication received in the first control message, receive a secondcontrol message within a control region of a second TTI that has asecond duration that is less than the first duration, wherein the firstTTI and the second TTI at least partially overlap in time, and receivedata in a data region of the second TTI based at least in part on agrant of resources received in the second control message, wherein thedata region of the first TTI is frequency division multiplexed with thedata region of the second TTI, and wherein the control region of thesecond TTI is frequency division multiplexed with the data region of thesecond TTI.

A non-transitory computer readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to receive a first controlmessage within a control region of a first TTI that has a firstduration, identify a data region of the first TTI based at least in parton an indication received in the first control message, receive a secondcontrol message within a control region of a second TTI that has asecond duration that is less than the first duration, wherein the firstTTI and the second TTI at least partially overlap in time, and receivedata in a data region of the second TTI based at least in part on agrant of resources received in the second control message, wherein thedata region of the first TTI is frequency division multiplexed with thedata region of the second TTI, and wherein the control region of thesecond TTI is frequency division multiplexed with the data region of thesecond TTI.

Another method of wireless communication is described. The method mayinclude receiving a control message within a control region of a TTI,identifying a downlink resource grant for the UE at a first position ofthe control region that is defined relative to a first boundary of thecontrol region, the downlink resource grant indicating resourcesassigned to the UE in a data region of the TTI, and monitoring for anuplink resource grant for the UE at a second position of the controlregion that is defined relative to a second boundary of the controlregion.

Another apparatus for wireless communication is described. The apparatusmay include means for receiving a control message within a controlregion of a TTI, means for identifying a downlink resource grant for theUE at a first position of the control region that is defined relative toa first boundary of the control region, the downlink resource grantindicating resources assigned to the UE in a data region of the TTI, andmeans for monitoring for an uplink resource grant for the UE at a secondposition of the control region that is defined relative to a secondboundary of the control region.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to receive a control message within acontrol region of a TTI, identify a downlink resource grant for the UEat a first position of the control region that is defined relative to afirst boundary of the control region, the downlink resource grantindicating resources assigned to the UE in a data region of the TTI, andmonitor for an uplink resource grant for the UE at a second position ofthe control region that is defined relative to a second boundary of thecontrol region.

Another non-transitory computer readable medium for wirelesscommunication is described. The non-transitory computer-readable mediummay include instructions operable to cause a processor to receive acontrol message within a control region of a TTI, identify a downlinkresource grant for the UE at a first position of the control region thatis defined relative to a first boundary of the control region, thedownlink resource grant indicating resources assigned to the UE in adata region of the TTI, and monitor for an uplink resource grant for theUE at a second position of the control region that is defined relativeto a second boundary of the control region.

Another method of wireless communication is described. The method mayinclude receiving a control message within a control region of a firstresource element block of a TTI, wherein the control message includesone or more resource allocation bits, receiving data in a first dataregion of the first resource element block based at least in part on theone or more resource allocation bits, determining that a second dataregion of a second resource element block of the TTI is allocated to theUE based at least in part on the one or more resource allocation bits,and receiving data in the second data region based at least in part onthe determination.

Another apparatus for wireless communication is described. The apparatusmay include means for receiving a control message within a controlregion of a first resource element block of a TTI, wherein the controlmessage includes one or more resource allocation bits, means forreceiving data in a first data region of the first resource elementblock based at least in part on the one or more resource allocationbits, means for determining that a second data region of a secondresource element block of the TTI is allocated to the UE based at leastin part on the one or more resource allocation bits, and means forreceiving data in the second data region based at least in part on thedetermination.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to receive a control message within acontrol region of a first resource element block of a TTI, wherein thecontrol message includes one or more resource allocation bits, receivedata in a first data region of the first resource element block based atleast in part on the one or more resource allocation bits, determinethat a second data region of a second resource element block of the TTIis allocated to the UE based at least in part on the one or moreresource allocation bits, and receive data in the second data regionbased at least in part on the determination.

Another non-transitory computer readable medium for wirelesscommunication is described. The non-transitory computer-readable mediummay include instructions operable to cause a processor to receive acontrol message within a control region of a first resource elementblock of a TTI, wherein the control message includes one or moreresource allocation bits, receive data in a first data region of thefirst resource element block based at least in part on the one or moreresource allocation bits, determine that a second data region of asecond resource element block of the TTI is allocated to the UE based atleast in part on the one or more resource allocation bits, and receivedata in the second data region based at least in part on thedetermination.

Another method of wireless communication is described. The method mayinclude transmitting a first control message within a control region ofa first TTI that has a first duration, wherein the control region of thefirst TTI includes an indication to be used by a UE to identify a dataregion within the first TTI, transmitting data in a data region of asecond TTI that has a second duration that is less than the firstduration, wherein the first TTI and the second TTI at least partiallyoverlap in time, wherein the data region of the first TTI is frequencydivision multiplexed with the data region of the second TTI, and whereinthe control region of the second TTI is frequency division multiplexedwith the data region of the second TTI, and transmitting a secondcontrol message within a control region of the second TTI, wherein thesecond control message includes a grant of resources for the transmitteddata in the data region of the second TTI, and wherein a location of thecontrol region of the second TTI is indicated in the first controlmessage.

Another apparatus for wireless communication is described. The apparatusmay include means for transmitting a first control message within acontrol region of a first TTI that has a first duration, wherein thecontrol region of the first TTI includes an indication to be used by aUE to identify a data region within the first TTI, means fortransmitting data in a data region of a second TTI that has a secondduration that is less than the first duration, wherein the first TTI andthe second TTI at least partially overlap in time, wherein the dataregion of the first TTI is frequency division multiplexed with the dataregion of the second TTI, and wherein the control region of the secondTTI is frequency division multiplexed with the data region of the secondTTI, and means for transmitting a second control message within acontrol region of the second TTI, wherein the second control messageincludes a grant of resources for the transmitted data in the dataregion of the second TTI, and wherein a location of the control regionof the second TTI is indicated in the first control message.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to transmit a first control messagewithin a control region of a first TTI that has a first duration,wherein the control region of the first TTI includes an indication to beused by a UE to identify a data region within the first TTI, transmitdata in a data region of a second TTI that has a second duration that isless than the first duration, wherein the first TTI and the second TTIat least partially overlap in time, wherein the data region of the firstTTI is frequency division multiplexed with the data region of the secondTTI, and wherein the control region of the second TTI is frequencydivision multiplexed with the data region of the second TTI, andtransmit a second control message within a control region of the secondTTI, wherein the second control message includes a grant of resourcesfor the transmitted data in the data region of the second TTI, andwherein a location of the control region of the second TTI is indicatedin the first control message.

Another non-transitory computer readable medium for wirelesscommunication is described. The non-transitory computer-readable mediummay include instructions operable to cause a processor to transmit afirst control message within a control region of a first TTI that has afirst duration, wherein the control region of the first TTI includes anindication to be used by a UE to identify a data region within the firstTTI, transmit data in a data region of a second TTI that has a secondduration that is less than the first duration, wherein the first TTI andthe second TTI at least partially overlap in time, wherein the dataregion of the first TTI is frequency division multiplexed with the dataregion of the second TTI, and wherein the control region of the secondTTI is frequency division multiplexed with the data region of the secondTTI, and transmit a second control message within a control region ofthe second TTI, wherein the second control message includes a grant ofresources for the transmitted data in the data region of the second TTI,and wherein a location of the control region of the second TTI isindicated in the first control message.

Another method of wireless communication is described. The method mayinclude generating a downlink resource grant that indicates resourcesassigned to a UE in a data region of a TTI and generating an uplinkresource grant for the UE and transmitting a control message within acontrol region of the TTI, wherein the control message includes thedownlink resource grant at a first position of the control region thatis defined relative to a first boundary of the control region and theuplink resource grant at a second position of the control region that isdefined relative to a second boundary of the control region.

Another apparatus for wireless communication is described. The apparatusmay include means for generating a downlink resource grant thatindicates resources assigned to a UE in a data region of a TTI, meansfor generating an uplink resource grant for the UE and means fortransmitting a control message within a control region of the TTI,wherein the control message includes the downlink resource grant at afirst position of the control region that is defined relative to a firstboundary of the control region and the uplink resource grant at a secondposition of the control region that is defined relative to a secondboundary of the control region.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to generate a downlink resource grantthat indicates resources assigned to a UE in a data region of a TTI,generate an uplink resource grant for the UE and transmit a controlmessage within a control region of the TTI, wherein the control messageincludes the downlink resource grant at a first position of the controlregion that is defined relative to a first boundary of the controlregion and the uplink resource grant at a second position of the controlregion that is defined relative to a second boundary of the controlregion.

Another non-transitory computer readable medium for wirelesscommunication is described. The non-transitory computer-readable mediummay include instructions operable to cause a processor to generate adownlink resource grant that indicates resources assigned to a UE in adata region of a TTI, generate an uplink resource grant for the UE andtransmit a control message within a control region of the TTI, whereinthe control message includes the downlink resource grant at a firstposition of the control region that is defined relative to a firstboundary of the control region and the uplink resource grant at a secondposition of the control region that is defined relative to a secondboundary of the control region.

Another method of wireless communication is described. The method mayinclude generating a control message for a first data region and asecond data region of a TTI, wherein the control message includes one ormore resource allocation bits to be used by a UE to determine that thefirst data region and the second data region are allocated to the UE,transmitting the control message in a control region of a first resourceelement block of the TTI, and transmitting, based at least in part onthe one or more resource allocation bits, data in the first data regionof the first resource element block of the TTI and data in the seconddata region of a second resource element block of the TTI.

Another apparatus for wireless communication is described. The apparatusmay include means for generating a control message for a first dataregion and a second data region of a TTI, wherein the control messageincludes one or more resource allocation bits to be used by a UE todetermine that the first data region and the second data region areallocated to the UE, means for transmitting the control message in acontrol region of a first resource element block of the TTI, and meansfor transmitting, based at least in part on the one or more resourceallocation bits, data in the first data region of the first resourceelement block of the TTI and data in the second data region of a secondresource element block of the TTI.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to generate a control message for afirst data region and a second data region of a TTI, wherein the controlmessage includes one or more resource allocation bits to be used by a UEto determine that the first data region and the second data region areallocated to the UE, transmit the control message in a control region ofa first resource element block of the TTI, and transmit, based at leastin part on the one or more resource allocation bits, data in the firstdata region of the first resource element block of the TTI and data inthe second data region of a second resource element block of the TTI.

Another non-transitory computer readable medium for wirelesscommunication is described. The non-transitory computer-readable mediummay include instructions operable to cause a processor to generate acontrol message for a first data region and a second data region of aTTI, wherein the control message includes one or more resourceallocation bits to be used by a UE to determine that the first dataregion and the second data region are allocated to the UE, transmit thecontrol message in a control region of a first resource element block ofthe TTI, and transmit, based at least in part on the one or moreresource allocation bits, data in the first data region of the firstresource element block of the TTI and data in the second data region ofa second resource element block of the TTI.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationthat supports downlink control channel structures for low latencyapplications in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system thatsupports downlink control channel structures for low latencyapplications in accordance with aspects of the present disclosure.

FIGS. 3-5B illustrate examples of resource allocation diagrams thatsupport downlink control channel structures for low latency applicationsin accordance with aspects of the present disclosure.

FIG. 6 illustrates an example of an uplink search space that supportsdownlink control channel structures for low latency applications inaccordance with aspects of the present disclosure.

FIGS. 7 through 9 show block diagrams of a device that supports downlinkcontrol channel structures for low latency applications in accordancewith aspects of the present disclosure.

FIG. 10 illustrates a block diagram of a system including a UE thatsupports downlink control channel structures for low latencyapplications in accordance with aspects of the present disclosure.

FIGS. 11 through 13 show block diagrams of a device that supportsdownlink control channel structures for low latency applications inaccordance with aspects of the present disclosure.

FIG. 14 illustrates a block diagram of a system including a base stationthat supports downlink control channel structures for low latencyapplications in accordance with aspects of the present disclosure.

FIGS. 15 through 20 illustrate methods for downlink control channelstructures for low latency applications in accordance with aspects ofthe present disclosure.

DETAILED DESCRIPTION

Control channels for low latency transmissions may be designed, mapped,and communicated to decrease signaling overhead and to increase theavailability of resources for low latency data channels. Data channelsusing reduced length transmission time intervals (TTIs) (e.g., includinga shortened TTI (sTTI)) may encounter a number of challenges includingthe need to efficiently support multiple low latency users as well aslegacy users, while allowing for the efficient reception and decoding ofcontrol information. A sTTI may include multiple resource blocks fordownlink transmissions of data. Certain resources within the sTTI mayhave already been allocated for other types of transmission. Suchnon-low latency transmissions that may be scheduled within the sTTI mayinclude legacy data transmissions in a physical downlink control channel(PDSCH) within a portion of the system bandwidth also used by the lowlatency users, narrowband internet-of-things (NB-IOT) type transmission,or common signals, such as a cell-specific reference signal (CRS),primary synchronization signal (PSS), secondary synchronization signal(SSS), or physical broadcast channel (PBCH), or other signals reservedby higher level signaling, such as radio resource control (RRC)signaling.

Efficient coexistence between low latency and non-low latencytransmissions may increase capacity and transmission efficiency. Acontrol region may be located at the beginning of a resource block, anda user equipment (UE) may receive and decode the control information todetermine that the data region of the resource block has been allocatedfor that UE. Mechanisms to provide for efficient reception and decodingof this control information are desired. In addition, reducing the sizeof the control region, or otherwise maximizing the size of the dataregion of the resource block relative to the control region, or eveneliminating one or more of the control regions from one or more of theresource blocks of the sTTI to minimize the impact of control overheadare desired.

In one example, a first control message in a control region of a firstTTI may provide an indication to identify a data region of the firstTTI. A data region of a second TTI may then be identified based on agrant of resources received in a second control message of the secondTTI (e.g., a sTTI), where the data region of the first TTI and thecontrol region of the second TTI are frequency division multiplexed withthe data region of the second TTI. The data region of the first TTI maybe a non-low latency transmission such that a receiving UE may ratematch the data region of the section TTI around the data region of thefirst TTI to receive low latency data. This technique may improveefficiency and support coexistence between low latency and non-lowlatency transmission with little impact on control overhead.

In another example, a downlink grant may be transmitted at the beginningof a control message in a control region of a sTTI, and uplink grantsmay be transmitted at the end of the control region. A configuration forthe downlink control message that anchors the downlink grant at thebeginning of the control region, and anchors the one or more uplinkgrants, if any, at the end of the downlink control message, may reducethe number of blind decodes that a receiving UE needs to perform, and/orallow for the processing of the downlink grant to begin prior to the UEcompleting searching for uplink grants. Thus, processing time andlatency may be optimized. In addition, in some cases, one or more bitsmay be added (e.g., to an information field) to a downlink grant toindicate a position within the control region for the start of theuplink grants. This indication may allow for a number of differentaggregation levels to be used, while allowing for unused portions of thecontrol region to be reallocated as part of the data region.

In other examples, a sTTI may include a number of resource blocks, eachof which may be assigned to a low latency user. In some cases, adownlink grant, which may be included in a control message in a controlregion at the beginning of a resource block, may be used to indicate theallocation of the data region of that resource block to a particularuser. A number of bits corresponding to the number of other resourceblocks (e.g., the total number of resource blocks of the sTTI minus one)may be added to the downlink grant to indicate whether the downlinkgrant may also be subsequent resource blocks in the sTTI. As such,control channel overhead may be reduced by reducing a total number ofdownlink grants, while minorly changing the total size of each downlinkgrant.

Aspects of the disclosure introduced above are described below in thecontext of a wireless communications system. Resource allocationdiagrams are then used to illustrate aspects of the disclosure. Aspectsof the disclosure are further illustrated by and described withreference to apparatus diagrams, system diagrams, and flowcharts thatrelate to downlink control channel structure for low latencyapplications.

FIG. 1 illustrates an example of a wireless communications system 100 inaccordance with various aspects of the present disclosure. The wirelesscommunications system 100 includes base stations 105, UEs 115, and acore network 130. In some examples, the wireless communications system100 may be a Long Term Evolution (LTE) (or LTE-Advanced) network.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Each base station 105 may providecommunication coverage for a respective geographic coverage area 110.Communication links 125 shown in wireless communications system 100 mayinclude UL transmissions from a UE 115 to a base station 105, or DLtransmissions from a base station 105 to a UE 115. UEs 115 may bedispersed throughout the wireless communications system 100, and each UE115 may be stationary or mobile. A UE 115 may also be referred to as amobile station, a subscriber station, a mobile unit, a subscriber unit,a wireless unit, a remote unit, a mobile device, a wireless device, awireless communications device, a remote device, a mobile subscriberstation, an access terminal, a mobile terminal, a wireless terminal, aremote terminal, a handset, a user agent, a mobile client, a client, orsome other suitable terminology. A UE 115 may also be a cellular phone,a personal digital assistant (PDA), a wireless modem, a wirelesscommunication device, a handheld device, a tablet computer, a laptopcomputer, a cordless phone, a personal electronic device, a handhelddevice, a personal computer, a wireless local loop (WLL) station, anInternet of things (IoT) device, an Internet of Everything (IoE) device,a machine type communication (MTC) device, an appliance, an automobile,or the like.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., S1, etc.). Base stations105 may communicate with one another over backhaul links 134 (e.g., X2,etc.) either directly or indirectly (e.g., through core network 130).Base stations 105 may perform radio configuration and scheduling forcommunication with UEs 115, or may operate under the control of a basestation controller (not shown). In some examples, base stations 105 maybe macro cells, small cells, hot spots, or the like. Base stations 105may also be referred to as eNodeBs (eNBs) 105.

In some cases, a base station 105 and a UE 115 may communicate usingmore than one carrier. Each aggregated carrier is referred to as acomponent carrier (CC). Each component can have a bandwidth of, e.g.,1.4, 3, 5, 10, 15 or 20 MHz. In some cases, the number of CCs can belimited to, e.g., a maximum of five 20 MHz carriers, giving a maximumaggregated bandwidth of 100 MHz. In frequency division duplexing (FDD),the number of aggregated carriers can be different in downlink (DL) anduplink (UL). The number of UL component carriers may be equal to orlower than the number of DL component carriers. The individual componentcarriers can also be of different bandwidths. For time divisionduplexing (TDD), the number of CCs as well as the bandwidths of each CCwill normally be the same for DL and UL. Component carriers may bearranged in a number of ways. For example, a carrier aggregation (CA)configuration may be based on contiguous component carriers within thesame operating frequency band, i.e., called intra-band contiguous CA.Non-contiguous allocations can also be used, where the componentcarriers may be either be intra-band, or inter-band.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include CDMA systems, TDMA systems, FDMAsystems, and OFDMA systems. A wireless multiple-access communicationssystem may include a number of base stations, each simultaneouslysupporting communication for one or more multiple communication devices,which may be otherwise known as UEs.

A base station 105 may communicate with one or more of UEs 115 using lowlatency transmissions, for example using sTTIs. A sTTI may be dividedinto a number of resource blocks, one or more of which may include acontrol region. The control region may include a downlink grant for alow latency UE 115, for example indicating a data region of the resourceblock is for the UE 115 to receive data.

In some examples, a first TTI may include a control region, for examplea PDCCH, that includes an indication of a data region within the firstTTI. The data region of the first TTI may be for a PDSCH, NB-IOT, orcommon signaling transmission, such as a PSS, SSS, CRS, or PBCH,transmitted by a base station 105. The first TTI may overlap at least inpart with a second TTI. The second TTI may be a shortened TTI (sTTI)made up of one or more resource blocks for low latency transmissions,where the data region within the first TTI punctures or otherwise fallswithin one or more of the resource blocks of the second TTI. A controlregion of the second TTI may be a shortened PDCCH (sPDCCH) for receptionby a low latency UE 115. The control region may include a controlmessage that has a grant of downlink resources for the UE 115, where thegrant indicates a data region of a resource block of the second TTI suchthat the indicated data region is frequency division multiplexed withthe data region of the first TTI. A UE 115 that receives the downlinkgrant in the sPDCCH may identify the data region of the first TTI, whichmay be for other UEs 115, and the data region for the low latency UE115, and rate match around the data region of the first TTI to receivelow latency data in the data region of the second TTI.

In other examples, a downlink grant transmitted in the control region ofa resource block may be both for the resource block in which thedownlink grant is sent by a base station 105 (or received at a UE 115)and for a second resource block within the same TTI. In particular, thedownlink grant may include an indication (e.g., a field made up of anumber of bits that is one less than the total number of resource blocksin the TTI) to inform the UE 115 that the downlink grant, in addition tobeing for data to be received by the UE 115 in a data region of theresource block, is also for the UE 115 to receive data in a data regionof one or more of the other resource blocks in the TTI.

In addition to a downlink grant in a control region of the TTI, thecontrol region may include one or more uplink grants. In some cases, oneor more of the uplink grants may be for the same UE 115, as the downlinkgrant. In some other cases, one or more of the uplink grants may be fora different set of UEs 115. In some cases, the downlink grant may be atthe beginning of the control region, for example, against a firstboundary of the control region; and the one or more uplink grants may beat the end of the control region, against a second boundary of thecontrol region. In some cases, the size of the control region may belarge enough so that, for the different possible aggregation levels,uplink grants and the downlink grant do not overlap in the controlregion. An unused portion of the control region, such as for loweraggregation levels, may be reallocated to the data region. In somecases, an indication of the start of the uplink grants may be providedin the downlink grant of the control region so that, in conjunction withknowledge provided by the UE 115 of the end of its downlink grant, theUE 115 may identify the reallocated data region within the controlregion.

FIG. 2 illustrates an example of a wireless communications system 200for downlink control channel structures for low latency applications.Wireless communications system 200 includes base station 105-a and UE115-a, which may be examples of aspects of a base station 105 and a UE115, as described with reference to FIG. 1. Base station 105-a maytransmit resource allocations and other control information in one ormore sPDCCH transmissions to the UE 115-a. The resource allocations mayinclude one or both of downlink grants and uplink grants of resourcesfor transmission of downlink data (e.g., in a sPDSCH) and uplink data(e.g., in a sPUSCH) for the UE 115-a. Wireless communications system 200may support non-low latency communication 205 and a low latencycommunication 210. Resources for the low latency communication 210 maybe time division multiplexed and/or frequency division multiplexed withthe non-low latency communication 205.

A sTTI for low latency communications may have multiple resource blocks,which may span the whole system bandwidth or a portion of the systembandwidth. The resource blocks may have the same or different sizes infrequency domain. Each resource block may be allocated for a single useror multiple users. The users may access one, multiple, or all of theresource blocks of the sTTI, depending on their configuration. Theresource block structure used may be defined by higher level signaling,for example, for a semi-static configuration.

A resource block may have a sPDCCH associated with the resource block.The sPDCCH may be embedded in the resource block. The sPDCCH may be atthe beginning of the resource block (e.g., in the first one or moresymbols of the resource block) to enable early decoding of the sPDCCH inthe resource block. The sPDCCH may span the bandwidth of the resourceblock, or may occupy less than the full bandwidth of the resource block,with additional signaling included above (e.g., at a higher frequency)and/or below (e.g., at a lower frequency) the resource elements occupiedby the sPDCCH in the resource block.

In some cases, a sPDCCH may allocate a sPDSCH to a low latency user fora resource block that has already been allocated to a PDSCH for someother users (e.g., legacy users) in a TTI. The TTI may overlap in wholeor in part with at least one sTTI. That is, a PDSCH allocation of a TTImay overlap in whole or in part with a resource block of a sTTI. Atransmission with a PDCCH (e.g., which may be referred to as a legacy orregular PDCCH) for a TTI may include an indication of the PDSCH resourceallocation within the TTI. For example, a PDSCH indicated by the PDCCHmay be allocated to a set of frequency resources. A low latency user maybe configured to monitor for such PDCCHs (e.g., receive and decodelegacy PDCCHs) in addition to sPDCCHs. The low latency user may thusreceive and decode the indication in the PDCCH and identify the PDSCHresource allocation.

In some cases, the low latency user may also receive a sPDCCHidentifying a sPDSCH of a resource block of a sTTI for the low latencyuser. Furthermore, in some cases, the resource block may also include aregular, or legacy PDSCH resource allocation. In some cases, the lowlatency user, having received the indication for the PDSCH, maydetermine a location of the PDSCH within the sTTI. Based on theindication, the low latency user may then determine that the sPDSCHassociated with the sPDCCH that the low latency user has received, forexample based on a downlink grant in the sPDCCH, is frequency divisionmultiplexed with the regular or legacy PDSCH. Thus, the low latency usermay receive low latency data in a sPDSCH, even in the presence of alegacy PDSCH resource allocation within the sTTI, by monitoring for andidentifying an indicator in the legacy or regular PDCCH.

In other cases, a sPDCCH for one resource block within a sTTI for a usermay include a downlink grant for one or more additional resource blockswithin the sTTI for the same user. For example, as described above, thesPDCCH may be in the first portion of the sTTI block (e.g., in the firstsymbol of the sTTI) at a predefined location within the resource blockof the sTTI. A low latency user may monitor the control region (e.g.,the sPDCCH) for each sTTI resource blocks to determine whether adownlink grant of resources has been sent (e.g., from a serving basestation 105-a) in the sPDCCH to the low latency user. A low latency usermay search for both uplink and downlink grants in the sPDCCH. In someexamples, a two stage grant for the low latency user may be used, wherethe first stage grant, received in messaging sent during a time intervalprior to the sTTI, specifies an aggregation level associated with theresource blocks of the sTTI.

As described above, a sPDCCH may be positioned at the beginning of aresource block of a sTTI. In addition, a downlink grant of the sPDCCHmay be positioned at the beginning of the sPDCCH. By providing thedownlink grant for a low latency user in a same position of each sPDCCH,a search space for the low latency user may be reduced. In someexamples, if a low latency user searches for a control message (e.g.,for a downlink grant of resources) for that user in a sPDCCH, andsuccessfully identifies the presence of a downlink grant, the lowlatency user may infer that the associated sPDSCH of that resource blockis allocated for that low latency user. Thus, the low latency user mayefficiently identify the sPDSCH allocated to itself.

In some cases, the downlink grant may include one or more bits thatpoint to other resource blocks of the sTTI comprising a sPDSCH, for thatsame low latency user. In some cases, the one or more bits may includeresource assignment information. Each of the one or more bits mayindicate whether or not a resource block is allocated for the same lowlatency user. For example, if a sTTI includes three resource blocks, twodownlink grant bits in a sPDSCH of one resource block may be used toindicate whether the downlink grant is for any of the other threeresource blocks for the low latency user.

In some cases, downlink grants in other resource blocks may be for oneor more other low latency users, and may likewise indicate that thesPDSCH in the resource block containing the sPDCCH with the downlinkgrant is for one or more of the other low latency user, and one or morebits (e.g., two bits for three resource blocks) may be used to indicatewhether any of the other resource blocks are for one or more of theother low latency users. The bits may be appropriately indexed and theresource block to which they relate may be based on a position of theresource block in which the one or more bits of the downlink grantappear. The above-described procedure may efficiently indicate downlinkgrants, at least in part, because a low latency user may only need toperform a blind decode in a fixed position of the sPDCCH within theresource block, and a number of blind decodes used to determine thedownlink grant may be limited to a number of resource blocks configuredby a base station 105-a in the sTTI.

As described above, a downlink grant may have a position at thebeginning of a sPDCCH. In some cases, one or more uplink grants for lowlatency users may be positioned in a sPDSCH of a sTTI that alreadycontains a downlink grant for a low latency user, where the uplink grantmay be for a different low latency user than the low latency user thatthe downlink grant is for. As described above, a first stage grant mayspecify an aggregation level. The one or more uplink grants may be sentat the specified aggregation level. Where other aggregation levels arespecified, the uplink grants may be sent according to other specifiedaggregation levels.

The uplink grants of a sPDCCH already containing a downlink grant may beseparated from the downlink grants. For example, the downlink grants maybe transmitted at the beginning of the sPDCCH control region, and theuplink grants may be sent at the end of the sPDCCH control region. Asused herein, the sPDCCH control region may be a virtual control region,for example meaning that the resource elements of the sPDCCH may not allbe adjacent in the time-frequency domain. The downlink and uplink grantsof a sPDCCH may be separated at least in part so that the downlink anduplink grant search spaces do not overlap. Providing the downlink grantat a fixed position relative to a boundary of the sPDCCH control region,and uplink grants at a fixed position relative to another boundary ofthe sPDCCH control region may reduce the number of blind decode attemptsfor a low latency user. In addition, because a downlink grant may bereceived at a set or predetermined position that is separated from asearch space for the one or more uplink grants, UE 115-a may begin todecode the downlink grant prior to completing a blind decoding processfor the uplink grants. In some cases, downlink grant processing anduplink grant blind decoding may proceed in parallel, thus increasingefficiency by decreasing the amount of time needed for the UE 115-a toreceive and process a sPDCCH.

A position of each of the uplink grants to be transmitted in a sPDCCHmay be determined by the base station 105-a based at least in part onthe uplink grant aggregation level. As described above, the base station105-a may transmit an indication of the uplink grant aggregation levelto a low latency user in a prior grant message. The base station 105-amay statically define uplink grant locations for each of multipleaggregation levels. In other examples, multiple uplink grant locationsmay be defined for a particular aggregation level. Multiple uplink grantlocations may result in a greater number of blind decoding attempts bythe UE 115-a, since there are an increased number of potential uplinkgrant locations for the UE 115-a.

In some examples, the size of the sPDCCH control region may be at leastlarge enough to accommodate a nominal level of grants and aggregationlevels without overlap of the downlink grants and uplink grants at thevarious aggregation levels. As such, a portion of the sPDCCH controlregion may be unused. The size of the unused portion of the sPDCCHcontrol region may depend on a number of uplink grants and theaggregation level for a particular sPDCCH. This unused sPDCCH controlregion may be repurposed by including an indication in the downlinkgrant of the sPDCCH (e.g., a sPDCCH rate matching information field)that indicates the start of the uplink grants in the sPDCCH. The UE115-a that holds the downlink grant may rate match the sPDSCH dataregion around the downlink grant and uplink grants, if any, to use thisotherwise unallocated portion of the sPDCCH as an additional portion ofthe sPDSCH. The size of this indicator may provide the number ofavailable positions to start the uplink grants in the sPDCCH. Forexample, where the indicator includes three bits, one of eight possiblepositions for the start of the uplink grants may be indicated.

FIG. 3 illustrates an example of a resource allocation diagram 300 fordownlink control channel structures for low latency applications.Resource allocation diagram 300 shows a system bandwidth 305, and twosTTIs: sTTI 310 and sTTI 315. In some cases, sTTI 310 and sTTI 315 maybe examples of low latency communication 210 described with reference toFIG. 2. Each sTTI is associated with two resource blocks, resource block320 and resource block 325. The resource blocks 320 and 325 need notnecessarily span the system bandwidth 305. For example, unallocatedregion 380 and unallocated region 385 in sTTI 310 and sTTI 315,respectively, may be within the system bandwidth, but not allocated aslow latency resource blocks.

In some cases, PDCCH 330, which in some examples may be included at thestart of a subframe, may be transmitted by a base station 105 for a TTIassociated with the starting subframe. In some other cases, PDCCH 330,which may be a legacy or non-legacy PDCCH may allocate resources withinthe TTI. In particular, in resource allocation diagram 300, PDCCH 330may allocate PDSCH 360. In some cases, PDCCH 330 may include a controlmessage receivable by a low latency user, and indicate an allocation ofPDSCH 360 within the system bandwidth 305. PDSCH 360 may have a durationof 1 ms in some examples.

Base station 105 may allocate resource block 320 and resource block 325of sTTI 310 to a low latency user, UE A; resource block 320 of sTTI 315to a low latency user, UE B; and resource block 325 of sTTI 315 to a lowlatency user, UE C. The base station 105 may include sPDCCH 335allocating resources (e.g., by including a first DL grant in the sPDCCH335) to sPDSCH 340 for UE A in a control region of resource block 320 ofsTTI 310. In addition, sPDCCH 335 may allocate resources (e.g., byincluding a second DL grant in the sPDCCH 335) to sPDSCH 355 for UE A ina control region of resource block 325 of sTTI 310. In this example,base station 105 may frequency division multiplex sPDSCH 355 with PDSCH360, such that a sPDSCH 355 may include portions both above and belowPDSCH 360 in frequency. The base station 105 may provide a controlmessage, for example, an indication in PDCCH 330 that it has allocatedPDSCH 360 to UE A. In some cases, the receiving UE A may then monitorfor and read the indication in PDCCH 330 that PDSCH 360 has beenallocated to UE A. In such cases, after receiving the downlink grant insPDCCH 335, the UE A may prepare to receive data in the sPDSCH 355 dataregion on either side of PDSCH 360.

In sTTI 315, sPDCCH 345 may allocate resources for sPDSCH 350 inresource block 320, and sPDCCH 365 may allocate resources for sPDSCH 370in resource block 325. In this example, base station 105 may frequencydivision multiplex both sPDCCH 365 and sPDSCH 370 with PDSCH 360, suchthat sPDCCH 365 includes portions both above and below PDSCH 360 infrequency, and sPDSCH 370 includes portions both above and below PDSCH360 in frequency. In some cases, receiving UE C may monitor for and,receive the indication in PDCCH 330 that PDSCH 360 has an allocation insTTI 315. UE C then monitors for and receives the control message ofsPDCCH 365 to determine that UE C has an allocated sPDSCH 370 andreceives data in the sPDSCH 370 data region on either side of PDSCH 360.

Similarly, a sPDCCH and/or sPDSCH may be frequency division multiplexedaround other signals transmitted during sTTI 310 and sTTI 315 asillustrated in resource allocation diagram 300. In one example, a NB-IOTtransmission 375 may be reserved to be sent during sTTI 310 and sTTI 315by RRC signaling. Base station 105 may frequency division multiplex (orrate match) around NB-IOT signaling 375. In other example, one or moreresource blocks may be reserved for a common signal, for example a CRS,PSS, SSS, or PBCH, or other signals reserved by higher level signaling,such as RRC signaling.

As described above, the control message in the legacy PDCCH in one TTImay identify a data region such as a PDSCH or NB-IOT, or commonsignaling, such as PSS, SSS, CRS, or PBCH, that a low latency user (orUE 115) may use to identify a resource allocation in a sTTI containingone or more resource blocks allocated to the low latency user. The lowlatency user may then receive low latency data, for example in a PDSCH,of a data region of one or more of the resource blocks, where the datais frequency domain multiplexed with the data region identified by thecontrol message in the legacy PDCCH.

FIG. 4 illustrates an example of a resource allocation diagram 400 fordownlink control channel structures for low latency applications.Resource allocation diagram 400 may include sTTI 410 occupying a systembandwidth 405. In some cases, the sTTI 410 may represent a sTTI within alegacy TTI, or a separate TTI. In some examples, and as may be the casewith other sTTIs described here, sTTI 410 may be of different durations.For example, in some cases, sTTI 410 may be spread over a single symbolperiod, or two symbol periods, or a single slot width associated with alegacy TTI, or another time period. In this example, sTTI 410 includesfour resource blocks: resource block 415 and resource block 430 for UEA, and resource block 420 and resource block 425 for UE B.

A base station 105 may generate a downlink grant 435 to be included in asPDCCH 440, the control region of resource block 415. In some cases, asPDSCH 445 may be in a first symbol period of the resource block 415. Insome cases, the downlink grant 435 may be in a data region of theresource block 415. The downlink grant may also be for a second sPDSCH,sPDSCH 450, in a data region of resource block 430 that are also for UEA, to be jointly used to receive data at UE A based on the controlinformation of downlink grant 435.

A base station 105 may also generate a second downlink grant 455 to beincluded in a sPDCCH 460, the control region of resource block 425. Thedownlink grant 455 may be for the sPDSCH 470 of the resource block 425,and may also be for the sPDSCH for resource block 420.

For both downlink grants, one or more bits in each of downlink grant 435and downlink grant 455 may be generated by a base station 105 toindicate other resource blocks of the sTTI that include a sPDSCH forthat same low latency user. In this example, sTTI 410 includes fourresource blocks. Downlink grant 435 for the UE A may thus include threebits to indicate whether the downlink grant 435 is for any of the otherthree resource blocks for the UE A.

In one example, the bits of the indication may make up or be a part of aresource allocation field in the downlink grant 435. In other examples,the bits of the indication may be included at another position in asPDCCH, such as sPDCCH 440, or elsewhere within the control region of aresource block, such as resource block 415. The first bit of theindication may be associated with resource block 420, the second bit maybe associated with resource block 425, and the third bit may beassociated with resource block 430. The receiving UEs, UE A and UE B mayinfer the relationship between the bits and the resource blocks. Forexample, the first bit may be associated with the first resource blockof the sTTI 410 that does not contain the downlink grant having the bitsof the indication, and so on. In the example shown in resourceallocation diagram 400 with respect to sTTI 410, in downlink grant 435,the third bit of the indication may identify the fourth resource block430 as for UE A. In downlink grant 455, the second bit of the indicationmay identify the second resource block 420 as for UE B.

The above-described procedure may efficiently indicate downlink grantsat least in part because a low latency user may only need to perform ablind decode in a fixed position of the sPDCCH within the resourceblock, and a number of blind decodes used to determine the downlinkgrant may be limited to a number of resource blocks configured by a basestation (e.g., cell) in the sTTI. Furthermore, the maximum number ofbits in the indication of the downlink grant may also be limited to thenumber of resource blocks of the sTTI minus one.

FIGS. 5A and 5B illustrate examples of resource allocation diagrams 501and 502 for downlink control channel structures for low latencyapplications.

Each of resource allocation diagrams 501 and 502 show a resource block505 for a sTTI 510, where the resource block 505 includes a controlregion including sPDCCH 515 and a data region including sPDSCH 525 forUE A that is indicated by sPDCCH 515. In some cases, sPDCCH 515 maycomprise or include one or more aspects of sPDCCH 335, sPDCCH 345,sPDCCH 365, sPDCCH 440, and sPDCCH 460. Furthermore, in some cases,sPDCCH 515 may include at least one downlink grant 520 for the UE A.Some examples of a sPDCCH 515 may include one more uplink grants for oneor more UEs, which may also include an uplink grant for the UE A. Insome examples, resource allocation diagrams 501 and 502 may includeuplink grant 530 for UE A, or uplink grant 535 for UE B, or uplink grant540 for UE C, or a combination thereof.

As illustrated in resource allocation diagrams 501 and 502, a downlinkgrant 520 may be at the beginning of the sPDCCH 515, for example, at aposition at a first boundary of the sPDCCH 515 control region. In somecases, the uplink grants may be clustered at the end of the controlregion, sPDCCH 515. The uplink grants may be transmitted by a basestation 105 in sPDCCH 515 of resource block 505 according to one ofmultiple different aggregation levels for UE A. In some examples, theaggregation level for UE A may have been indicated in a previouslytransmitted grant from base station 105. For example, a two-stage grantconfiguration may be used, such that the first grant in a previoustransmission (e.g., a previous sTTI or TTI, such as a PDCCH in apreviously-received TTI) may include the aggregation level for UE A, andthe second grant may be the downlink grant 520. The uplink grant 530,uplink grant 535, and uplink grant 540 may be at the end of sPDCCH 515,with the uplink grant 530 for UE A at the end of sPDCCH 515 and locatedat a position at a second boundary of the sPDCCH 515 control region. Insome cases, as depicted, uplink grant 535 and uplink grant 540 may be atpositions adjacent to the uplink grant 530 for the UE A. In some cases,the span of sPDCCH 515 may be wide enough such that for any aggregationlevel that can be indicated for the UE A, the downlink grant 520 andmultiple uplink grants may not overlap if the downlink grant 520 is atthe beginning of sPDCCH 515 and the uplink grant(s)s are positioned atthe end of sPDCCH 515.

The configuration of downlink grants at the beginning of sPDCCH 515 anduplink grants at the end of sPDCCH 515, may reduce the number of blinddecoding attempts for a particular UE. For example, one downlink grantfor the particular UE may be at the beginning of sPDCCH 515. If anattempted blind decode at the beginning of sPDCCH is unsuccessful, theUE may deduce that the sPDSCH 525 is not for that particular UE.

As illustrated in resource allocation diagram 502, a portion of thecontrol region for sPDCCH 515 may be reallocated to be a part of dataregion for sPDSCH 525, thus recapturing unused control overhead fromsPDCCH 515. Thus, reallocated sPDSCH 545 may be relocated from a portionof the sPDCCH 515-a between downlink grant 520-a and the uplink grants,specifically an uplink grant 535-a for UE B. The size of reallocatedsPDSCH 545 may depend in part on the aggregation level. The resources ofsPDCCH 515-a that are to be used for reallocated sPDSCH 545 may besignaled in the downlink grant 520-a. In particular, an indication mayidentify the start of the uplink grant region, which may include uplinkgrant 530-a, uplink grant 535-a, and uplink grant 540-a for sPDCCH515-a. In some examples, the indication may be rate matching informationfield, as further described below.

FIG. 6 illustrates an example of an uplink search space 600 for downlinkcontrol channel structures for low latency applications. In some cases,uplink search space 600 may represent an uplink search space for asPDCCH that may be or include one or more aspects of sPDCCH 335, sPDCCH345, sPDCCH 365, sPDCCH 440, sPDCCH 460, and sPDCCH 515. The uplinksearch space 600 is shown for four aggregation levels, including a firstaggregation level 610, a second aggregation level 615, a thirdaggregation level 620, and a fourth aggregation level 625. As describedabove, the uplink grants may be positioned at a the end of a sPDCCHcontrol region, as indicated by boundary 605. An uplink grant for a UE Amay be transmitted at the first aggregation level 610, an uplink grantfor UE B may be transmitted at the second aggregation level 615, and anuplink grant for UE C may be transmitted at the third aggregation level620.

As described above, a base station 105 may provide an indication to oneor more UEs 115, identifying the start of the uplink grant region, whichmay include uplink grant 645 for UE A, uplink grant 655 for UE B, anduplink grant 645 for UE C. The indication may be a rate matchinginformation field in a downlink grant, for example downlink grant 690for the UE B transmitted at the second aggregation level 615. Asillustrated for uplink search space 600, the indication may be at leastthree bits in length to identify one of eight different positions 695.In this example, downlink grant 690 for the UE B is transmitted at thesecond aggregation level 615 and includes an indication of ‘5’ toindicate that the start of the uplink grant region is at the fifthposition of positions 695. Furthermore, UE B having received itsdownlink grant 690 may then deduce that a region 685 of the PDCCHcontrol region may be suitable or usable for sPDSCH transmissions. Insome cases, as shown, region 685 may exist between the end of thedownlink grant 690 for UE B and the fifth position of positions 695.

In other implementations, a greater or fewer number of positions for thestart of the uplink grants may be indicated in the downlink grant. Agreater number of positions 695 may be indicated by adding one or morebits, for example by increasing the size of the rate matchinginformation field to four or more bits. Increasing the number ofpositions 695 may increase scheduling flexibility, but may also increasethe number of blind decode attempts for a UE receiver to search foruplink grants, thus increasing the overhead. Similarly, a smaller numberof positions 695 may be indicated (e.g., four positions using two bitsin the downlink grant), decreasing flexibility, but also decreasingoverhead and the number of blind decode attempts for a UE receiver.

FIG. 7 shows a block diagram 700 of a wireless device 705 that supportsdownlink control channel structures for low latency applications inaccordance with various aspects of the present disclosure. Wirelessdevice 705 may be an example of aspects of a UE 115 as described withreference to FIGS. 1 and 2. Wireless device 705 may include receiver710, UE DL control manager 715, and transmitter 720. Wireless device 705may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

Receiver 710 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to downlinkcontrol channel structure for low latency applications, etc.).Information may be passed on to other components of the device. Thereceiver 710 may be an example of aspects of the transceiver 1035described with reference to FIG. 10.

UE DL control manager 715 may be an example of aspects of the UE DLcontrol manager 1015 described with reference to FIG. 10.

UE DL control manager 715 may receive a first control message within acontrol region of a first TTI that has a first duration, identify a dataregion of the first TTI based on an indication received in the firstcontrol message, receive a second control message within a controlregion of a second TTI that has a second duration that is less than thefirst duration, where the first TTI and the second TTI at leastpartially overlap in time, and receive data in a data region of thesecond TTI based on a grant of resources received in the second controlmessage, where the data region of the first TTI is frequency divisionmultiplexed with the data region of the second TTI, and where thecontrol region of the second TTI is frequency division multiplexed withthe data region of the second TTI.

In some cases, the UE DL control manager 715 may also receive a controlmessage within a control region of a TTI, identify a downlink resourcegrant for the UE at a first position of the control region that isdefined relative to a first boundary of the control region, the downlinkresource grant indicating resources assigned to the UE in a data regionof the TTI, and monitor for an uplink resource grant for the UE at asecond position of the control region that is defined relative to asecond boundary of the control region.

Furthermore, in some other cases, the UE DL control manager 715 may alsoreceive a control message within a control region of a first resourceelement block of a TTI, where the control message includes one or moreresource allocation bits, receive data in a first data region of thefirst resource element block based on the one or more resourceallocation bits, determine that a second data region of a secondresource element block of the TTI is allocated to the UE based on theone or more resource allocation bits, and receive data in the seconddata region based on the determination.

Transmitter 720 may transmit signals generated by other components ofthe device. In some examples, the transmitter 720 may be collocated witha receiver 710 in a transceiver module. For example, the transmitter 720may be an example of aspects of the transceiver 1035 described withreference to FIG. 10. The transmitter 720 may include a single antenna,or it may include a set of antennas.

FIG. 8 shows a block diagram 800 of a wireless device 805 that supportsdownlink control channel structures for low latency applications inaccordance with various aspects of the present disclosure. Wirelessdevice 805 may be an example of aspects of a wireless device 705 or a UE115 as described with reference to FIGS. 1 and 7. Wireless device 805may include receiver 810, UE DL control manager 815, and transmitter820. Wireless device 805 may also include a processor. Each of thesecomponents may be in communication with one another (e.g., via one ormore buses).

Receiver 810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to downlinkcontrol channel structure for low latency applications, etc.).Information may be passed on to other components of the device. Thereceiver 810 may be an example of aspects of the transceiver 1035described with reference to FIG. 10.

UE DL control manager 815 may be an example of aspects of the UE DLcontrol manager 1015 described with reference to FIG. 10. UE DL controlmanager 815 may also include control message component 825, data regionidentifier 830, data receiver 835, DL grant component 840, and grantmonitoring component 845.

Control message component 825 may receive a first control message withina control region of a first TTI that has a first duration, receive asecond control message within a control region of a second TTI that hasa second duration that is less than the first duration, where the firstTTI and the second TTI at least partially overlap in time, receive acontrol message within a control region of a TTI, receive a controlmessage within a control region of a first resource element block of aTTI, where the control message includes one or more resource allocationbits, identify a position of the second resource element block withinthe TTI based on the one or more resource allocation bits, and monitorfor the control message with one or more data regions of the TTI, wherethe control message is received based on determining that the controlmessage passes a cyclic redundancy check.

In some cases, the control region of the second TTI includes a shortenedphysical downlink control channel (physical downlink control channel(PDCCH)). In some cases, the data region of the first TTI includes aPDSCH or a NB-IOT region. In some cases, a duration of the second TTIincludes an integer number of symbol periods or one slot.

Data region identifier 830 may identify a data region of the first TTIbased on an indication received in the first control message, identify aportion of the data region of the TTI between the first position and thesecond position of the control region, and determine that a second dataregion of a second resource element block of the TTI is allocated to theUE based on the one or more resource allocation bits.

Data receiver 835 may receive data in a data region of the second TTIbased on a grant of resources received in the second control message,where the data region of the first TTI is frequency division multiplexedwith the data region of the second TTI, and where the control region ofthe second TTI is frequency division multiplexed with the data region ofthe second TTI, receive data in a first data region of the firstresource element block based on the one or more resource allocationbits, and receive data in the second data region based on thedetermination. In some cases, a location of the control region of thesecond TTI is indicated in the first control message. In some cases, thedata region of the second TTI includes a sPDSCH.

DL grant component 840 may identify a downlink resource grant for the UEat a first position of the control region that is defined relative to afirst boundary of the control region, the downlink resource grantindicating resources assigned to the UE in a data region of the TTI and,receive in the downlink resource grant an uplink grant positionindicator that indicates the second position of the control region. Insome cases, the downlink resource grant includes an information fieldthat includes the uplink grant position indicator. In some cases, thefirst boundary includes a logical starting point of the control regionrelative to the TTI.

Grant monitoring component 845 may monitor for an uplink resource grantfor the UE at a second position of the control region that is definedrelative to a second boundary of the control region and monitor for theuplink resource grant within the control region based on the aggregationlevel. In some cases, monitoring for the uplink resource grant for theUE includes: monitoring for the uplink resource grant for the UE at oneor more additional positions defined relative to the second boundary ofthe control region or the second position. In some cases, the secondboundary includes a logical end point of the control region relative tothe TTI.

Transmitter 820 may transmit signals generated by other components ofthe device. In some examples, the transmitter 820 may be collocated witha receiver 810 in a transceiver module. For example, the transmitter 820may be an example of aspects of the transceiver 1035 described withreference to FIG. 10. The transmitter 820 may include a single antenna,or it may include a set of antennas.

FIG. 9 shows a block diagram 900 of a UE DL control manager 915 thatsupports downlink control channel structures for low latencyapplications in accordance with various aspects of the presentdisclosure. The UE DL control manager 915 may be an example of aspectsof a UE DL control manager 715, a UE DL control manager 815, or a UE DLcontrol manager 1015 described with reference to FIGS. 7, 8, and 10. TheUE DL control manager 915 may include control message component 920,data region identifier 925, data receiver 930, DL grant component 935,grant monitoring component 940, rate matcher 945, resource allocationcomponent 950, UL grant component 955, aggregation component 960, andbit allocation component 965. Each of these modules may communicate,directly or indirectly, with one another (e.g., via one or more buses).

In some cases, control message component 920 may receive a first controlmessage within a control region of a first TTI that has a firstduration, and receive a second control message within a control regionof a second TTI that has a second duration that is less than the firstduration. In some cases, the first TTI and the second TTI may partiallyoverlap in time. Furthermore, in some cases, control message component920 may receive a control message within a control region of a TTI(e.g., a first resource element block of a TTI), wherein the controlmessage includes one or more resource allocation bits, identify aposition of the second resource element block within the TTI based onthe one or more resource allocation bits, and monitor for the controlmessage with one or more data regions of the TTI, where the controlmessage is received based on determining that the control message passesa cyclic redundancy check.

In some cases, the control region of the second TTI includes a sPDCCH.In some cases, the data region of the first TTI includes a PDSCH or aNB-IOT region. In some cases, a duration of the second TTI includes aninteger number of symbol periods or one or more slots.

Data region identifier 925 may identify a data region of the first TTIbased on an indication received in the first control message, identify aportion of the data region of the TTI between the first position and thesecond position of the control region, and determine that a second dataregion of a second resource element block of the TTI is allocated to theUE based on the one or more resource allocation bits.

Data receiver 930 may receive data in a data region of the second TTIbased on a grant of resources received in the second control message,where the data region of the first TTI is frequency division multiplexedwith the data region of the second TTI, and where the control region ofthe second TTI is frequency division multiplexed with the data region ofthe second TTI. Furthermore, in some cases, data receiver 930 mayreceive data in a first data region of the first resource element blockbased on the one or more resource allocation bits, and receive data inthe second data region based on the determination. In some cases, alocation of the control region of the second TTI is indicated in thefirst control message. In some cases, the data region of the second TTIincludes a sPDSCH.

DL grant component 935 may identify a downlink resource grant for the UEat a first position of the control region that is defined relative to afirst boundary of the control region, the downlink resource grantindicating resources assigned to the UE in a data region of the TTI and,receive in the downlink resource grant an uplink grant positionindicator that indicates the second position of the control region. Insome cases, the downlink resource grant includes an information fieldthat includes the uplink grant position indicator. In some cases, thefirst boundary includes a logical starting point of the control regionrelative to the TTI.

Grant monitoring component 940 may monitor for an uplink resource grantfor the UE at a second position of the control region that is definedrelative to a second boundary of the control region and monitor for theuplink resource grant within the control region based on the aggregationlevel. In some cases, monitoring for the uplink resource grant for theUE includes: monitoring for the uplink resource grant for the UE at oneor more additional positions defined relative to the second boundary ofthe control region or the second position. In some cases, the secondboundary includes a logical end point of the control region relative tothe TTI.

Rate matcher 945 may be responsible for data region rate matching. Insome cases, receiving the data in the data region of the second TTIincludes: rate matching around the data region of the first TTI. In somecases, receiving the second control message within the control region ofthe second TTI includes: rate matching around the data region of thefirst TTI.

Resource allocation component 950 may identify an additional resourceallocation that at least partially overlaps in time with the second TTIand is frequency division multiplexed with the data region of the firstTTI and the data region of the second TTI.

UL grant component 955 may identify the second position of the controlregion based on the uplink grant position indicator.

Aggregation component 960 may determine an aggregation level associatedwith the control region.

Bit allocation component 965 may identify a number of bits associatedwith the one or more resource allocation bits and determine a number ofresource element blocks of the TTI based on the identified number ofbits.

FIG. 10 shows a diagram of a system 1000 including a device 1005 thatsupports downlink control channel structures for low latencyapplications in accordance with various aspects of the presentdisclosure. Device 1005 may be an example of or include the componentsof wireless device 705, wireless device 805, or a UE 115 as describedabove, e.g., with reference to FIGS. 1, 7 and 8. Device 1005 may includecomponents for bi-directional voice and data communications includingcomponents for transmitting and receiving communications, including UEDL control manager 1015, processor 1020, memory 1025, software 1030,transceiver 1035, antenna 1040, and I/O controller 1045. Thesecomponents may be in electronic communication via one or more busses(e.g., bus 1010). Device 1005 may communicate wirelessly with one ormore base stations 105.

Processor 1020 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a digital signal processor (DSP), a centralprocessing unit (CPU), a microcontroller, an application-specificintegrated circuit (ASIC), an field-programmable gate array (FPGA), aprogrammable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, processor 1020 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into processor 1020. Processor 1020 may be configured toexecute computer-readable instructions stored in a memory to performvarious functions (e.g., functions or tasks supporting downlink controlchannel structure for low latency applications).1020.

Memory 1025 may include random access memory (RAM) and read only memory(ROM). The memory 1025 may store computer-readable, computer-executablesoftware 1030 including instructions that, when executed, cause theprocessor to perform various functions described herein. In some cases,the memory 1025 may contain, among other things, a basic input/outputsystem (BIOS) which may control basic hardware and/or software operationsuch as the interaction with peripheral components or devices.

Software 1030 may include code to implement aspects of the presentdisclosure, including code to support downlink control channel structurefor low latency applications. Software 1030 may be stored in anon-transitory computer-readable medium such as system memory or othermemory. In some cases, the software 1030 may not be directly executableby the processor but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

Transceiver 1035 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1035 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1035 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1040.However, in some cases the device may have more than one antenna 1040,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

I/O controller 1045 may manage input and output signals for device 1005.I/O controller 1045 may also manage peripherals not integrated intodevice 1005. In some cases, I/O controller 1045 may represent a physicalconnection or port to an external peripheral. In some cases, I/Ocontroller 1045 may utilize an operating system such as iOS®, ANDROID®,MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operatingsystem.

FIG. 11 shows a block diagram 1100 of a wireless device 1105 thatsupports downlink control channel structures for low latencyapplications in accordance with various aspects of the presentdisclosure. Wireless device 1105 may be an example of aspects of a basestation 105 as described with reference to FIG. 1. Wireless device 1105may include receiver 1110, base station DL control manager 1115, andtransmitter 1120. Wireless device 1105 may also include a processor.Each of these components may be in communication with one another (e.g.,via one or more buses).

Receiver 1110 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to downlinkcontrol channel structure for low latency applications, etc.).Information may be passed on to other components of the device. Thereceiver 1110 may be an example of aspects of the transceiver 1435described with reference to FIG. 14.

Base station DL control manager 1115 may be an example of aspects of thebase station DL control manager 1415 described with reference to FIG.14.

Base station DL control manager 1115 may transmit a first controlmessage within a control region of a first TTI that has a firstduration, where the control region of the first TTI includes anindication to be used by a UE to identify a data region within the firstTTI, and transmit data in a data region of a second TTI that has asecond duration that is less than the first duration, where the firstTTI and the second TTI at least partially overlap in time. In somecases, the data region of the first TTI is frequency divisionmultiplexed with the data region of the second TTI, and the controlregion of the second TTI is frequency division multiplexed with the dataregion of the second TTI. In some cases, base station DL control manager1115 may transmit a second control message within a control region ofthe second TTI, where the second control message includes a grant ofresources for the transmitted data in the data region of the second TTI,and where a location of the control region of the second TTI isindicated in the first control message.

In some cases, the base station DL control manager 1115 may alsogenerate a downlink resource grant that indicates resources assigned toa UE in a data region of a TTI and generate an uplink resource grant forthe UE and transmit a control message within a control region of theTTI, where the control message includes the downlink resource grant at afirst position of the control region that is defined relative to a firstboundary of the control region and the uplink resource grant at a secondposition of the control region that is defined relative to a secondboundary of the control region. The base station DL control manager 1115may also generate a control message for a first data region and a seconddata region of a TTI, where the control message includes one or moreresource allocation bits to be used by a UE to determine that the firstdata region and the second data region are allocated to the UE, transmitthe control message in a control region of a first resource elementblock of the TTI, and transmit, based on the one or more resourceallocation bits, data in the first data region of the first resourceelement block of the TTI and data in the second data region of a secondresource element block of the TTI.

Transmitter 1120 may transmit signals generated by other components ofthe device. In some examples, the transmitter 1120 may be collocatedwith a receiver 1110 in a transceiver module. For example, thetransmitter 1120 may be an example of aspects of the transceiver 1435described with reference to FIG. 14. The transmitter 1120 may include asingle antenna, or it may include a set of antennas.

FIG. 12 shows a block diagram 1200 of a wireless device 1205 thatsupports downlink control channel structures for low latencyapplications in accordance with various aspects of the presentdisclosure. Wireless device 1205 may be an example of aspects of awireless device 1105 or a base station 105 as described with referenceto FIGS. 1, 2 and 11. Wireless device 1205 may include receiver 1210,base station DL control manager 1215, and transmitter 1220. Wirelessdevice 1205 may also include a processor. Each of these components maybe in communication with one another (e.g., via one or more buses).

Receiver 1210 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to downlinkcontrol channel structure for low latency applications, etc.).Information may be passed on to other components of the device. Thereceiver 1210 may be an example of aspects of the transceiver 1435described with reference to FIG. 14.

Base station DL control manager 1215 may be an example of aspects of thebase station DL control manager 1415 described with reference to FIG.14.

Base station DL control manager 1215 may also include control messagecomponent 1225, data transmitter 1230, and DL grant component 1235.

Control message component 1225 may transmit a first control messagewithin a control region of a first TTI that has a first duration, wherethe control region of the first TTI includes an indication to be used bya UE to identify a data region within the first TTI, transmit a secondcontrol message within a control region of the second TTI, where thesecond control message includes a grant of resources for the transmitteddata in the data region of the second TTI, and where a location of thecontrol region of the second TTI is indicated in the first controlmessage.

In some other cases, control message component 1225 may transmit acontrol message within a control region of the TTI, where the controlmessage includes the downlink resource grant at a first position of thecontrol region that is defined relative to a first boundary of thecontrol region and the uplink resource grant at a second position of thecontrol region that is defined relative to a second boundary of thecontrol region.

Furthermore, in some cases, control message component 1225 may generatea control message for a first data region and a second data region of aTTI, where the control message includes one or more resource allocationbits to be used by a UE to determine that the first data region and thesecond data region are allocated to the UE, and transmit the controlmessage in a control region of a first resource element block of theTTI.

Data transmitter 1230 may transmit data in a data region of a second TTIthat has a second duration that is less than the first duration, wherethe first TTI and the second TTI at least partially overlap in time,where the data region of the first TTI is frequency division multiplexedwith the data region of the second TTI, and where the control region ofthe second TTI is frequency division multiplexed with the data region ofthe second TTI and transmit, based on the one or more resourceallocation bits, data in the first data region of the first resourceelement block of the TTI and data in the second data region of a secondresource element block of the TTI.

DL grant component 1235 may generate a downlink resource grant thatindicates resources assigned to a UE in a data region of a TTI andgenerate an uplink resource grant for the UE.

Transmitter 1220 may transmit signals generated by other components ofthe device. In some examples, the transmitter 1220 may be collocatedwith a receiver 1210 in a transceiver module. For example, thetransmitter 1220 may be an example of aspects of the transceiver 1435described with reference to FIG. 14. The transmitter 1220 may include asingle antenna, or it may include a set of antennas.

FIG. 13 shows a block diagram 1300 of a base station DL control manager1315 that supports downlink control channel structures for low latencyapplications in accordance with various aspects of the presentdisclosure. The base station DL control manager 1315 may be an exampleof aspects of a base station DL control manager 1415 described withreference to FIGS. 11, 12, and 14. The base station DL control manager1315 may include control message component 1320, data transmitter 1325,and DL grant component 1330. Each of these modules may communicate,directly or indirectly, with one another (e.g., via one or more buses).

Control message component 1320 may transmit a first control messagewithin a control region of a first TTI that has a first duration, wherethe control region of the first TTI includes an indication to be used bya UE to identify a data region within the first TTI, transmit a secondcontrol message within a control region of the second TTI, where thesecond control message includes a grant of resources for the transmitteddata in the data region of the second TTI, and where a location of thecontrol region of the second TTI is indicated in the first controlmessage.

Furthermore, in some cases, control message component 1320 may transmita control message within a control region of the TTI, where the controlmessage includes the downlink resource grant at a first position of thecontrol region that is defined relative to a first boundary of thecontrol region and the uplink resource grant at a second position of thecontrol region that is defined relative to a second boundary of thecontrol region, generate a control message for a first data region and asecond data region of a TTI, where the control message includes one ormore resource allocation bits to be used by a UE to determine that thefirst data region and the second data region are allocated to the UE,and transmit the control message in a control region of a first resourceelement block of the TTI.

Data transmitter 1325 may transmit data in a data region of a second TTIthat has a second duration that is less than the first duration, wherethe first TTI and the second TTI at least partially overlap in time,where the data region of the first TTI is frequency division multiplexedwith the data region of the second TTI, and where the control region ofthe second TTI is frequency division multiplexed with the data region ofthe second TTI and transmit, based on the one or more resourceallocation bits, data in the first data region of the first resourceelement block of the TTI and data in the second data region of a secondresource element block of the TTI.

DL grant component 1330 may generate a downlink resource grant thatindicates resources assigned to a UE in a data region of a TTI andgenerate an uplink resource grant for the UE.

FIG. 14 shows a diagram of a system 1400 including a device 1405 thatsupports downlink control channel structures for low latencyapplications in accordance with various aspects of the presentdisclosure. Device 1405 may be an example of or include the componentsof base station 105 as described above, e.g., with reference to FIG. 1.Device 1405 may include components for bi-directional voice and datacommunications including components for transmitting and receivingcommunications, including base station DL control manager 1415,processor 1420, memory 1425, software 1430, transceiver 1435, antenna1440, network communications manager 1445, and base stationcommunications manager 1450. These components may be in electroniccommunication via one or more busses (e.g., bus 1410). Device 1405 maycommunicate wirelessly with one or more UEs 115.

Processor 1420 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, aFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, processor 1420 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into processor 1420. Processor 1420 may be configured toexecute computer-readable instructions stored in a memory to performvarious functions (e.g., functions or tasks supporting downlink controlchannel structure for low latency applications).1420.

Memory 1425 may include RAM and ROM. The memory 1425 may storecomputer-readable, computer-executable software 1430 includinginstructions that, when executed, cause the processor to perform variousfunctions described herein. In some cases, the memory 1425 may contain,among other things, a BIOS which may control basic hardware and/orsoftware operation such as the interaction with peripheral components ordevices.

Software 1430 may include code to implement aspects of the presentdisclosure, including code to support downlink control channel structurefor low latency applications. Software 1430 may be stored in anon-transitory computer-readable medium such as system memory or othermemory. In some cases, the software 1430 may not be directly executableby the processor but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

Transceiver 1435 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1435 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1435 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1440.However, in some cases the device may have more than one antenna 1440,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

Network communications manager 1445 may manage communications with thecore network (e.g., via one or more wired backhaul links). For example,the network communications manager 1445 may manage the transfer of datacommunications for client devices, such as one or more UEs 115.

Base station communications manager 1450 may manage communications withother base station 105, and may include a controller or scheduler forcontrolling communications with UEs 115 in cooperation with other basestations 105. For example, the base station communications manager 1450may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, base station communications manager 1450may provide a X2 interface within a LTE/LTE-A wireless communicationnetwork technology to provide communication between base stations 105.

FIG. 15 shows a flowchart illustrating a method 1500 for downlinkcontrol channel structures for low latency applications in accordancewith various aspects of the present disclosure. The operations of method1500 may be implemented by a UE 115 or its components as describedherein. For example, the operations of method 1500 may be performed by aUE DL control manager as described with reference to FIGS. 7 through 10.In some examples, a UE 115 may execute a set of codes to control thefunctional elements of the device to perform the functions describedbelow. Additionally or alternatively, the UE 115 may perform aspects ofthe functions described below using special-purpose hardware.

At block 1505 the UE 115 may receive a first control message within acontrol region of a first TTI that has a first duration. The operationsof block 1505 may be performed according to the methods described withreference to FIGS. 1 through 6. In certain examples, aspects of theoperations of block 1505 may be performed by a control message componentas described with reference to FIGS. 7 through 10.

At block 1510 the UE 115 may identify a data region of the first TTIbased at least in part on an indication received in the first controlmessage. The operations of block 1510 may be performed according to themethods described with reference to FIGS. 1 through 6. In certainexamples, aspects of the operations of block 1510 may be performed by adata region identifier as described with reference to FIGS. 7 through10.

At block 1515 the UE 115 may receive a second control message within acontrol region of a second TTI that has a second duration that is lessthan the first duration, wherein the first TTI and the second TTI atleast partially overlap in time. The operations of block 1515 may beperformed according to the methods described with reference to FIGS. 1through 6. In certain examples, aspects of the operations of block 1515may be performed by a control message component as described withreference to FIGS. 7 through 10.

At block 1520 the UE 115 may receive data in a data region of the secondTTI based at least in part on a grant of resources received in thesecond control message, wherein the data region of the first TTI isfrequency division multiplexed with the data region of the second TTI,and wherein the control region of the second TTI is frequency divisionmultiplexed with the data region of the second TTI. The operations ofblock 1520 may be performed according to the methods described withreference to FIGS. 1 through 6. In certain examples, aspects of theoperations of block 1520 may be performed by a data receiver asdescribed with reference to FIGS. 7 through 10.

FIG. 16 shows a flowchart illustrating a method 1600 for downlinkcontrol channel structures for low latency applications in accordancewith various aspects of the present disclosure. The operations of method1600 may be implemented by a UE 115 or its components as describedherein. For example, the operations of method 1600 may be performed by aUE DL control manager as described with reference to FIGS. 7 through 10.In some examples, a UE 115 may execute a set of codes to control thefunctional elements of the device to perform the functions describedbelow. Additionally or alternatively, the UE 115 may perform aspects ofthe functions described below using special-purpose hardware.

At block 1605 the UE 115 may receive a control message within a controlregion of a TTI. The operations of block 1605 may be performed accordingto the methods described with reference to FIGS. 1 through 6. In certainexamples, aspects of the operations of block 1605 may be performed by acontrol message component as described with reference to FIGS. 7 through10.

At block 1610 the UE 115 may identify a downlink resource grant for theUE 115 at a first position of the control region that is definedrelative to a first boundary of the control region, the downlinkresource grant indicating resources assigned to the UE in a data regionof the TTI. The operations of block 1610 may be performed according tothe methods described with reference to FIGS. 1 through 6. In certainexamples, aspects of the operations of block 1610 may be performed by aDL grant component as described with reference to FIGS. 7 through 10.

At block 1615 the UE 115 may monitor for an uplink resource grant forthe UE 115 at a second position of the control region that is definedrelative to a second boundary of the control region. The operations ofblock 1615 may be performed according to the methods described withreference to FIGS. 1 through 6. In certain examples, aspects of theoperations of block 1615 may be performed by a grant monitoringcomponent as described with reference to FIGS. 7 through 10.

FIG. 17 shows a flowchart illustrating a method 1700 for downlinkcontrol channel structures for low latency applications in accordancewith various aspects of the present disclosure. The operations of method1700 may be implemented by a UE 115 or its components as describedherein. For example, the operations of method 1700 may be performed by aUE DL control manager as described with reference to FIGS. 7 through 10.In some examples, a UE 115 may execute a set of codes to control thefunctional elements of the device to perform the functions describedbelow. Additionally or alternatively, the UE 115 may perform aspects thefunctions described below using special-purpose hardware.

At block 1705 the UE 115 may receive a control message within a controlregion of a first resource element block of a TTI, wherein the controlmessage includes one or more resource allocation bits. The operations ofblock 1705 may be performed according to the methods described withreference to FIGS. 1 through 6. In certain examples, aspects of theoperations of block 1705 may be performed by a control message componentas described with reference to FIGS. 7 through 10.

At block 1710 the UE 115 may receive data in a first data region of thefirst resource element block based at least in part on the one or moreresource allocation bits. The operations of block 1710 may be performedaccording to the methods described with reference to FIGS. 1 through 6.In certain examples, aspects of the operations of block 1710 may beperformed by a data receiver as described with reference to FIGS. 7through 10.

At block 1715 the UE 115 may determine that a second data region of asecond resource element block of the TTI is allocated to the UE based atleast in part on the one or more resource allocation bits. Theoperations of block 1715 may be performed according to the methodsdescribed with reference to FIGS. 1 through 6. In certain examples,aspects of the operations of block 1715 may be performed by a dataregion identifier as described with reference to FIGS. 7 through 10.

At block 1720 the UE 115 may receive data in the second data regionbased at least in part on the determination. The operations of block1720 may be performed according to the methods described with referenceto FIGS. 1 through 6. In certain examples, aspects of the operations ofblock 1720 may be performed by a data receiver as described withreference to FIGS. 7 through 10.

FIG. 18 shows a flowchart illustrating a method 1800 for downlinkcontrol channel structures for low latency applications in accordancewith various aspects of the present disclosure. The operations of method1800 may be implemented by a base station 105 or its components asdescribed herein. For example, the operations of method 1800 may beperformed by a base station DL control manager as described withreference to FIGS. 11 through 14. In some examples, a base station 105may execute a set of codes to control the functional elements of thedevice to perform the functions described below. Additionally oralternatively, the base station 105 may perform aspects of the functionsdescribed below using special-purpose hardware.

At block 1805 the base station 105 may transmit a first control messagewithin a control region of a first TTI that has a first duration,wherein the control region of the first TTI includes an indication to beused by a UE to identify a data region within the first TTI. Theoperations of block 1805 may be performed according to the methodsdescribed with reference to FIGS. 1 through 6. In certain examples,aspects of the operations of block 1805 may be performed by a controlmessage component as described with reference to FIGS. 11 through 14.

At block 1810 the base station 105 may transmit data in a data region ofa second TTI that has a second duration that is less than the firstduration, wherein the first TTI and the second TTI at least partiallyoverlap in time, wherein the data region of the first TTI is frequencydivision multiplexed with the data region of the second TTI, and whereinthe control region of the second TTI is frequency division multiplexedwith the data region of the second TTI. The operations of block 1810 maybe performed according to the methods described with reference to FIGS.1 through 6. In certain examples, aspects of the operations of block1810 may be performed by a data transmitter as described with referenceto FIGS. 11 through 14.

At block 1815 the base station 105 may transmit a second control messagewithin a control region of the second TTI, wherein the second controlmessage includes a grant of resources for the transmitted data in thedata region of the second TTI, and wherein a location of the controlregion of the second TTI is indicated in the first control message. Theoperations of block 1815 may be performed according to the methodsdescribed with reference to FIGS. 1 through 6. In certain examples,aspects of the operations of block 1815 may be performed by a controlmessage component as described with reference to FIGS. 11 through 14.

FIG. 19 shows a flowchart illustrating a method 1900 for downlinkcontrol channel structures for low latency applications in accordancewith various aspects of the present disclosure. The operations of method1900 may be implemented by a base station 105 or its components asdescribed herein. For example, the operations of method 1900 may beperformed by a base station DL control manager as described withreference to FIGS. 11 through 14. In some examples, a base station 105may execute a set of codes to control the functional elements of thedevice to perform the functions described below. Additionally oralternatively, the base station 105 may perform aspects of the functionsdescribed below using special-purpose hardware.

At block 1905 the base station 105 may generate a downlink resourcegrant that indicates resources assigned to a UE in a data region of aTTI. The operations of block 1905 may be performed according to themethods described with reference to FIGS. 1 through 6. In certainexamples, aspects of the operations of block 1905 may be performed by aDL grant component as described with reference to FIGS. 11 through 14.

At block 1910 the base station 105 may generate an uplink resource grantfor the UE. The operations of block 1910 may be performed according tothe methods described with reference to FIGS. 1 through 6. In certainexamples, aspects of the operations of block 1910 may be performed by aDL grant component as described with reference to FIGS. 11 through 14.

At block 1915 the base station 105 may transmit a control message withina control region of the TTI, wherein the control message includes thedownlink resource grant at a first position of the control region thatis defined relative to a first boundary of the control region and theuplink resource grant at a second position of the control region that isdefined relative to a second boundary of the control region. Theoperations of block 1915 may be performed according to the methodsdescribed with reference to FIGS. 1 through 6. In certain examples,aspects of the operations of block 1915 may be performed by a controlmessage component as described with reference to FIGS. 11 through 14.

FIG. 20 shows a flowchart illustrating a method 2000 for downlinkcontrol channel structures for low latency applications in accordancewith various aspects of the present disclosure. The operations of method2000 may be implemented by a base station 105 or its components asdescribed herein. For example, the operations of method 2000 may beperformed by a base station DL control manager as described withreference to FIGS. 11 through 14. In some examples, a base station 105may execute a set of codes to control the functional elements of thedevice to perform the functions described below. Additionally oralternatively, the base station 105 may perform aspects the functionsdescribed below using special-purpose hardware.

At block 2005 the base station 105 may generate a control message for afirst data region and a second data region of a TTI, wherein the controlmessage includes one or more resource allocation bits to be used by a UEto determine that the first data region and the second data region areallocated to the UE. The operations of block 2005 may be performedaccording to the methods described with reference to FIGS. 1 through 6.In certain examples, aspects of the operations of block 2005 may beperformed by a control message component as described with reference toFIGS. 11 through 14.

At block 2010 the base station 105 may transmit the control message in acontrol region of a first resource element block of the TTI. Theoperations of block 2010 may be performed according to the methodsdescribed with reference to FIGS. 1 through 6. In certain examples,aspects of the operations of block 2010 may be performed by a controlmessage component as described with reference to FIGS. 11 through 14.

At block 2015 the base station 105 may transmit, based at least in parton the one or more resource allocation bits, data in the first dataregion of the first resource element block of the TTI and data in thesecond data region of a second resource element block of the TTI. Theoperations of block 2015 may be performed according to the methodsdescribed with reference to FIGS. 1 through 6. In certain examples,aspects of the operations of block 2015 may be performed by a datatransmitter as described with reference to FIGS. 11 through 14.

It should be noted that the methods described above describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Furthermore, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.The terms “system” and “network” are often used interchangeably. A CDMAsystem may implement a radio technology such as CDMA2000, UniversalTerrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95,and IS-856 standards. IS-2000 Releases may be commonly referred to asCDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An orthogonal frequency division multiple access (OFDMA) system mayimplement a radio technology such as Ultra Mobile Broadband (UMB),Evolved UTRA (E-UTRA), Institute of Electrical and Electronics Engineers(IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM,etc. UTRA and E-UTRA are part of Universal Mobile Telecommunicationssystem (UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A)are new releases of Universal Mobile Telecommunications System (UMTS)that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and Global System forMobile communications (GSM) are described in documents from theorganization named “3rd Generation Partnership Project” (3GPP). CDMA2000and UMB are described in documents from an organization named “3rdGeneration Partnership Project 2” (3GPP2). The techniques describedherein may be used for the systems and radio technologies mentionedabove as well as other systems and radio technologies. While aspects aLTE system may be described for purposes of example, and LTE terminologymay be used in much of the description, the techniques described hereinare applicable beyond LTE applications.

In LTE/LTE-A networks, including such networks described herein, theterm eNB may be generally used to describe the base stations. Thewireless communications system or systems described herein may include aheterogeneous LTE/LTE-A network in which different types of eNBs providecoverage for various geographical regions. For example, each eNB or basestation may provide communication coverage for a macro cell, a smallcell, or other types of cell. The term “cell” may be used to describe abase station, a carrier or component carrier associated with a basestation, or a coverage area (e.g., sector, etc.) of a carrier or basestation, depending on context.

Base stations may include or may be referred to by those skilled in theart as a base transceiver station, a radio base station, an accesspoint, a radio transceiver, a NodeB, eNodeB (eNB), Home NodeB, a HomeeNodeB, or some other suitable terminology. The geographic coverage areafor a base station may be divided into sectors making up only a portionof the coverage area. The wireless communications system or systemsdescribed herein may include base stations of different types (e.g.,macro or small cell base stations). The UEs described herein may be ableto communicate with various types of base stations and network equipmentincluding macro eNBs, small cell eNBs, relay base stations, and thelike. There may be overlapping geographic coverage areas for differenttechnologies.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell is alower-powered base station, as compared with a macro cell, that mayoperate in the same or different (e.g., licensed, unlicensed, etc.)frequency bands as macro cells. Small cells may include pico cells,femto cells, and micro cells according to various examples. A pico cell,for example, may cover a small geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell may also cover a small geographic area (e.g., ahome) and may provide restricted access by UEs having an associationwith the femto cell (e.g., UEs in a closed subscriber group (CSG), UEsfor users in the home, and the like). An eNB for a macro cell may bereferred to as a macro eNB. An eNB for a small cell may be referred toas a small cell eNB, a pico eNB, a femto eNB, or a home eNB. An eNB maysupport one or multiple (e.g., two, three, four, and the like) cells(e.g., component carriers). A UE may be able to communicate with varioustypes of base stations and network equipment including macro eNBs, smallcell eNBs, relay base stations, and the like.

The wireless communications system or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations may have similar frame timing, andtransmissions from different base stations may be approximately alignedin time. For asynchronous operation, the base stations may havedifferent frame timing, and transmissions from different base stationsmay not be aligned in time. The techniques described herein may be usedfor either synchronous or asynchronous operations.

The downlink transmissions described herein may also be called forwardlink transmissions while the uplink transmissions may also be calledreverse link transmissions. Each communication link describedherein—including, for example, wireless communications system 100 and200 of FIGS. 1 and 2—may include one or more carriers, where eachcarrier may be a signal made up of multiple sub-carriers (e.g., waveformsignals of different frequencies).

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the above description may berepresented by voltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any combinationthereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, a FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described above can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations. Also, as used herein, including in the claims, “or” as usedin a list of items (for example, a list of items prefaced by a phrasesuch as “at least one of” or “one or more of”) indicates an inclusivelist such that, for example, a list of at least one of A, B, or C meansA or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, asused herein, the phrase “based on” shall not be construed as a referenceto a closed set of conditions. For example, an exemplary step that isdescribed as “based on condition A” may be based on both a condition Aand a condition B without departing from the scope of the presentdisclosure. In other words, as used herein, the phrase “based on” shallbe construed in the same manner as the phrase “based at least in parton.”

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media maycomprise RAM, ROM, electrically erasable programmable read only memory(EEPROM), compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, or wirelesstechnologies such as infrared, radio, and microwave are included in thedefinition of medium. Disk and disc, as used herein, include CD, laserdisc, optical disc, digital versatile disc (DVD), floppy disk andBlu-ray disc where disks usually reproduce data magnetically, whilediscs reproduce data optically with lasers. Combinations of the aboveare also included within the scope of computer-readable media.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

All structural and functional equivalents to the elements of the variousaspects described throughout this disclosure that are known or latercome to be known to those of ordinary skill in the art are expresslyincorporated herein by reference and are intended to be encompassed bythe claims. Moreover, nothing disclosed herein is intended to bededicated to the public regardless of whether such disclosure isexplicitly recited in the claims. The words “module,” “mechanism,”“element,” “device,” “component,” and the like may not be a substitutefor the word “means.” As such, no claim element is to be construed as ameans plus function unless the element is expressly recited using thephrase “means for.”

What is claimed is:
 1. A method for wireless communication at a userequipment (UE), comprising: receiving a control message within a controlregion of a first resource element block of a transmission time interval(TTI), wherein the control message includes one or more resourceallocation bits; receiving data in a first data region of the firstresource element block based at least in part on the one or moreresource allocation bits; determining that a second data region of asecond resource element block of the TTI is allocated to the UE based atleast in part on the one or more resource allocation bits; and receivingdata in the second data region based at least in part on thedetermination.
 2. The method of claim 1, further comprising: identifyinga position of the second resource element block within the TTI based atleast in part on the one or more resource allocation bits.
 3. The methodof claim 1, further comprising: identifying a number of bits associatedwith the one or more resource allocation bits; and determining a numberof resource element blocks of the TTI based at least in part on theidentified number of bits.
 4. The method of claim 1, further comprising:monitoring for the control message with one or more data regions of theTTI, wherein the control message is received based at least in part ondetermining that the control message passes a cyclic redundancy check.5. A method for wireless communication at a base station, comprising:generating a control message for a first data region and a second dataregion of a transmission time interval (TTI), wherein the controlmessage includes one or more resource allocation bits to be used by auser equipment (UE) to determine that the first data region and thesecond data region are allocated to the UE; transmitting the controlmessage in a control region of a first resource element block of theTTI; and transmitting, based at least in part on the one or moreresource allocation bits, data in the first data region of the firstresource element block of the TTI and data in the second data region ofa second resource element block of the TTI.
 6. An apparatus for wirelesscommunication at a user equipment (UE), in a system comprising: aprocessor; memory in electronic communication with the processor; andinstructions stored in the memory and operable, when executed by theprocessor, to cause the apparatus to: receive a control message within acontrol region of a first resource element block of a transmission timeinterval (TTI), wherein the control message includes one or moreresource allocation bits; receive data in a first data region of thefirst resource element block based at least in part on the one or moreresource allocation bits; determine that a second data region of asecond resource element block of the TTI is allocated to the UE based atleast in part on the one or more resource allocation bits; and receivedata in the second data region based at least in part on thedetermination.
 7. The apparatus of claim 6, wherein the instructionsstored in the memory are further operable to cause the apparatus to:identify a position of the second resource element block within the TTIbased at least in part on the one or more resource allocation bits. 8.The apparatus of claim 6, wherein the instructions stored in the memoryare further operable to cause the apparatus to: identify a number ofbits associated with the one or more resource allocation bits; anddetermine a number of resource element blocks of the TTI based at leastin part on the identified number of bits.
 9. The apparatus of claim 6,wherein the instructions stored in the memory are further operable tocause the apparatus to: monitor for the control message with one or moredata regions of the TTI, wherein the control message is received basedat least in part on determining that the control message passes a cyclicredundancy check.
 10. An apparatus for wireless communication at a basestation, in a system comprising: a processor; memory in electroniccommunication with the processor; and instructions stored in the memoryand operable, when executed by the processor, to cause the apparatus to:generate a control message for a first data region and a second dataregion of a transmission time interval (TTI), wherein the controlmessage includes one or more resource allocation bits to be used by auser equipment (UE) to determine that the first data region and thesecond data region are allocated to the UE; transmit the control messagein a control region of a first resource element block of the TTI; andtransmit, based at least in part on the one or more resource allocationbits, data in the first data region of the first resource element blockof the TTI and data in the second data region of a second resourceelement block of the TTI.
 11. An apparatus for wireless communication ata user equipment (UE), comprising: means for receiving a control messagewithin a control region of a first resource element block of atransmission time interval (TTI), wherein the control message includesone or more resource allocation bits; means for receiving data in afirst data region of the first resource element block based at least inpart on the one or more resource allocation bits; means for determiningthat a second data region of a second resource element block of the TTIis allocated to the UE based at least in part on the one or moreresource allocation bits; and means for receiving data in the seconddata region based at least in part on the determination.
 12. Theapparatus of claim 11, further comprising: means for identifying aposition of the second resource element block within the TTI based atleast in part on the one or more resource allocation bits.
 13. Theapparatus of claim 11, further comprising: means for identifying anumber of bits associated with the one or more resource allocation bits;and means for determining a number of resource element blocks of the TTIbased at least in part on the identified number of bits.
 14. Theapparatus of claim 11, further comprising: means for monitoring for thecontrol message with one or more data regions of the TTI, wherein thecontrol message is received based at least in part on determining thatthe control message passes a cyclic redundancy check.
 15. An apparatusfor wireless communication at a base station, comprising: means forgenerating a control message for a first data region and a second dataregion of a transmission time interval (TTI), wherein the controlmessage includes one or more resource allocation bits to be used by auser equipment (UE) to determine that the first data region and thesecond data region are allocated to the UE; means for transmitting thecontrol message in a control region of a first resource element block ofthe TTI; and means for transmitting, based at least in part on the oneor more resource allocation bits, data in the first data region of thefirst resource element block of the TTI and data in the second dataregion of a second resource element block of the TTI.
 16. Anon-transitory computer readable medium storing code for wirelesscommunication at a user equipment (UE), the code comprising instructionsexecutable to: receive a control message within a control region of afirst resource element block of a transmission time interval (TTI),wherein the control message includes one or more resource allocationbits; receive data in a first data region of the first resource elementblock based at least in part on the one or more resource allocationbits; determine that a second data region of a second resource elementblock of the TTI is allocated to the UE based at least in part on theone or more resource allocation bits; and receive data in the seconddata region based at least in part on the determination.
 17. Thenon-transitory computer readable medium of claim 16, wherein the codefurther comprises instructions executable to: means for identifying aposition of the second resource element block within the TTI based atleast in part on the one or more resource allocation bits.
 18. Thenon-transitory computer readable medium of claim 16, wherein the codefurther comprises instructions executable to: means for identifying anumber of bits associated with the one or more resource allocation bits;and means for determining a number of resource element blocks of the TTIbased at least in part on the identified number of bits.
 19. Thenon-transitory computer readable medium of claim 16, wherein the codefurther comprises instructions executable to: means for monitoring forthe control message with one or more data regions of the TTI, whereinthe control message is received based at least in part on determiningthat the control message passes a cyclic redundancy check.
 20. Anon-transitory computer readable medium storing code for wirelesscommunication at a base station, the code comprising instructionsexecutable to: generate a control message for a first data region and asecond data region of a transmission time interval (TTI), wherein thecontrol message includes one or more resource allocation bits to be usedby a user equipment (UE) to determine that the first data region and thesecond data region are allocated to the UE; transmit the control messagein a control region of a first resource element block of the TTI; andtransmit, based at least in part on the one or more resource allocationbits, data in the first data region of the first resource element blockof the TTI and data in the second data region of a second resourceelement block of the TTI.